title: Statin discontinuation and risk of acute myocardial infarction in patients with rheumatoid arthritis: a population-based cohort study.
abstract: OBJECTIVE
  Screening for cardiovascular risk factors and treating hyperlipidaemia with statins are recommended to reduce the increased cardiovascular risk in individuals with rheumatoid arthritis (RA). However, poor compliance with statins may limit their therapeutic benefit. Our objective was to evaluate the impact of statin discontinuation on risk of acute myocardial infarction (AMI) among RA patients.
  
  
  METHODS
  The authors conducted a population-based cohort study of RA patients with incident statin use followed from May 1996 to March 2006 using administrative health data. Primary exposure was statin discontinuation for ≥ 3 months at any time during therapy course. The authors used Cox's proportional hazards models and modelled statin discontinuation as a time-dependent variable, while adjusting for age, sex, comorbidities, use of other medications influencing cardiac risk, and proxy indicators of RA severity.
  
  
  RESULTS
  During 15 669 person-years of follow-up in 4102 incident-statin users with RA, the authors identified 264 AMI events. Statin discontinuation was associated with 67% increased risk of AMI (adjusted HR 1.67; 95% CI 1.24 to 2.25). There was a 2% increase in risk of AMI with each 1-month increase in the duration of discontinuation (adjusted HR 1.02; 95% CI 1.01 to 1.03). These associations were not modified by timing of first statin prescription, prior AMI status, sex and age (p values for interactions >0.17).
  
  
  CONCLUSIONS
  These population-based data indicate that RA patients who discontinue statins have increased risk of AMI. Findings emphasise the need to raise awareness, among health professionals and people with RA, of the importance of compliance with statin therapy in RA.
authors.affiliation: University of British Columbia School of Population & Public Health, Arthritis Research Centre of Canada, 895 W. 10th Avenue, Vancouver, BC, Canada V5Z 1L7. mdevera@arthritisresearch.ca
authors.forename: Mary A
authors.initials: MA
authors.lastname: De Vera
authors.forename: Hyon
authors.initials: H
authors.lastname: Choi
authors.forename: Michal
authors.initials: M
authors.lastname: Abrahamowicz
authors.forename: Jacek
authors.initials: J
authors.lastname: Kopec
authors.forename: Maria Victoria
authors.initials: MV
authors.lastname: Goycochea-Robles
authors.forename: Diane
authors.initials: D
authors.lastname: Lacaille
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001172:Arthritis, Rheumatoid / Q000150:complications* / Q000453:epidemiology; D001955:British Columbia / Q000453:epidemiology; D004812:Epidemiologic Methods; D005260:Female; D006801:Humans; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000008:administration & dosage* / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000453:epidemiology / Q000209:etiology* / Q000517:prevention & control; D055815:Young Adult; D016903:Drug Monitoring
chemical_list: D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors